Charging Model 3 via HPWC - "Voltage Too High"

[zkmusa]

I wanted to see if anyone has seen this same error recently.

I took my Model 3 to a hotel in Houston that is set up with 3 destination chargers. The hotel has a Model X as their hotel car, and they charge it at the destination chargers every night. In addition, plugshare has a checkin from a Model S user without issues charging the car.

When the hotel tried to charge my new Model 3, the car would attempt to start charging. The voltage would reach approx 280 volts (I believe it was 278 volts), then the car would immediately stop charging and say something along the lines of: "Cannot charge. Voltage too high." I attempt to reduce the charging current to as low as 15 amps, but the same error occurred.

What's interesting is that the Plugshare entry for this location (located here) has a screenshot from the Model S user, where the car is charging at 42 amps at 275 volts.

Two questions:
- How is it possible for an HPWC to even receive 275+ volts as an input, when the grid provides 240 volts? What am I missing here?
- Did the charger circuitry or software for the Model 3 change, so that's why the Model 3 was rejecting the charge, whereas an S/X don't have the same issue?

In the end, I had to drive out to a supercharger to charge.

Thanks for your help.

 

[dhrivnak]

Three phase current can be tricky and I suspect this charger was wired wrong as I would expect 208 volts. Sorry to hear of your troubles and different cars have different tolerances for charging.

 

[seattlite2004]

Sounds like they didn't use a transformer on their 3 phase supply.

 

[TexasEV]

The HPWCs that are connected to 277V three phase circuits will charge a Model S and Model X, but not a Model 3. This is a known issue.

 

[zkmusa]

The HPWCs that are connected to 277V three phase circuits will charge a Model S and Model X, but not a Model 3. This is a known issue.

Can you provide some more information about this? I couldn't find any other posts that mentioned the same issue with the Model 3.

 

[EfficientWatts]

Little known fact - gen 2 chargers initially had support for 277V single phase listed, but it was dropped. A thread with a link to the old revision of the install guide is here:

HPWC in Nashua - 80A@277V

It was unknown why it was dropped in the first place. Perhaps scenarios like what the model 3 saw explains it, though it doesn't explain why the model 3 sees a higher voltage vs the S and X. Could be the way it ramps up so initially the voltage is higher?

I think if the HPWC was hooked up to a 277V line that had lower voltage (like below 277V because of line quality) I think it would charge just fine.

Personally I think they should have made 277V fully supported, at least for NA.

 

[MP3Mike]

It was unknown why it was dropped in the first place. Perhaps scenarios like what the model 3 saw explains it, though it doesn't explain why the model 3 sees a higher voltage vs the S and X. Could be the way it ramps up so initially the voltage is higher?

Probably because the Model S was charging at 42 amps so there was some voltage sag, the Model 3 wasn't charging so it was at full voltage.

 

[Fiver]

Little known fact - gen 2 chargers initially had support for 277V single phase listed, but it was dropped. A thread with a link to the old revision of the install guide is here:

HPWC in Nashua - 80A@277V

It was unknown why it was dropped in the first place. Perhaps scenarios like what the model 3 saw explains it, though it doesn't explain why the model 3 sees a higher voltage vs the S and X. Could be the way it ramps up so initially the voltage is higher?

I think if the HPWC was hooked up to a 277V line that had lower voltage (like below 277V because of line quality) I think it would charge just fine.

Personally I think they should have made 277V fully supported, at least for NA.

277v is found in industrial areas.

It was dropped from HPWC support because of the fault tolerance built into the internal chargers of the S and X. Yes they (the internal chargers) can handle 277v, but they trip for over-voltage on those at 283v. When charging at 240v that gives you a ton of headroom, but at 277v not so much. Apparently to reset them if you went 283v or above you had to go to a service center (I just read that, unsure if true).

So to be safe they just killed support for 277v. I think also at the time they killed them they also knew that Model 3 wouldn't support it with it's hardware, so they nipped it in the bud before too many 277v HPWC got installed.

I was bummed they killed support for it. We just put in a destination charger setup near me, and the install cost a lot more because they had to get special equipment to go from 277v down to 208v. It would have been nice to charge at 277v 80amp.

/edit I shouldn't say they killed support as in they made it no longer work... It still works fine for S&X if you have one set up for 277v, it's just Tesla won't provide support in that configuration.

 

[zkmusa]

Interesting. Thank you all for the info.

Is there any way of knowing how a destination charger is set up, and whether my Model 3 will charge on the destination charger, when I'm planning a trip that involves destination chargers?

 

[Fiver]

Interesting. Thank you all for the info.

Is there any way of knowing how a destination charger is set up, and whether my Model 3 will charge on the destination charger, when I'm planning a trip that involves destination chargers?

In North America there are only a handful of 277v HPWC, so I wouldn't worry too much. Check Plugshare.com, download the plugshare app on your phone (every EV driver should have it really) to see what chargers are around where you are going, a lot of times people list the voltage and amp output on there for chargers.

 

[EfficientWatts]

277v is found in industrial areas.

It was dropped from HPWC support because of the fault tolerance built into the internal chargers of the S and X. Yes they (the internal chargers) can handle 277v, but they trip for over-voltage on those at 283v. When charging at 240v that gives you a ton of headroom, but at 277v not so much. Apparently to reset them if you went 283v or above you had to go to a service center (I just read that, unsure if true).

So to be safe they just killed support for 277v. I think also at the time they killed them they also knew that Model 3 wouldn't support it with it's hardware, so they nipped it in the bud before too many 277v HPWC got installed.

I was bummed they killed support for it. We just put in a destination charger setup near me, and the install cost a lot more because they had to get special equipment to go from 277v down to 208v. It would have been nice to charge at 277v 80amp.

/edit I shouldn't say they killed support as in they made it no longer work... It still works fine for S&X if you have one set up for 277v, it's just Tesla won't provide support in that configuration.

That's what I thought. This was kind of discussed in another thread here where I was asking about 277V charging.

EV Charging Expansion and Voltage Limitations

One thing that I noted that the original gen 1 charger was rated up to 277V, then the gen 2 charger was rated up to 300V. The subsequent chargers (the generation with 48A/72A) don't have sticker ratings on them.

Given that it appears that similar tech is used in superchargers, it is reasonable to stand that the chargers could support a higher voltage range with some safety tolerance, though +10% would put it at 304.7V (though with a SC the input power is likely to be closer to 277V due to line quality). My guess is that at least for gen 2 (and onward if they carried similar ratings), over voltage protection may be more of a function of software limit than a hardware one.

 

[Fiver]

That's what I thought. This was kind of discussed in another thread here where I was asking about 277V charging.

EV Charging Expansion and Voltage Limitations

One thing that I noted that the original gen 1 charger was rated up to 277V, then the gen 2 charger was rated up to 300V. The subsequent chargers (the generation with 48A/72A) don't have sticker ratings on them.

Given that it appears that similar tech is used in superchargers, it is reasonable to stand that the chargers could support a higher voltage range with some safety tolerance, though +10% would put it at 304.7V (though with a SC the input power is likely to be closer to 277V due to line quality). My guess is that at least for gen 2 (and onward if they carried similar ratings), over voltage protection may be more of a function of software limit than a hardware one.

You know, the more I think about it... While voltage safety might have been a concern early on, I think really the primary reason they dropped support for 277v is because they knew Model 3 wouldn't support it out of the gate. It would suck to have a bunch of 277v HPWC out there that Model 3 couldn't use. It would only create confusion for buyers about some chargers not working while others do. Plus, in the grand scheme of things, 277v is pretty rare outside of industrial parks and the like, you don't see it in most standard commercial locations and never in residential. It's a niche thing so might as well just kill it before it got too widespread. (That, and the chance to fry your charger if you had a crappy 277v line that surged and fried the cars internal charger.)

 

[yuhong]

I wonder how much they would save by killing 277V support in the first place though.

 

[cellogig]

I am having the same problem with 277 charging at work. It is a Tesla destination charging that is listed on the Tesla website. This happened to me over a month and half ago.

We have a controller on board of our model 3 that shuts down charging if it senses anything over 250volts.

Tesla is aware of the problem....
Basically I was told will not be fixed at that particular destination. The problem is what other recommended Tesla destination chargers are not model 3 friendly.

I was also told there will be a list specifically for model 3 charging friendly put out by Tesla.

The more we report this issue hopefully it will have a resolution quicker

 

[Fiver]

I really wonder how many 277v HPWC are out there installed in the wild. I can't imagine it's more then 25-50 across all of North America.

 

[cellogig]

I really wonder how many 277v HPWC are out there installed in the wild. I can't imagine it's more then 25-50 across all of North America.

I have one at my work place

How can I get them to fix it correctly to accept a model 3 charge

 

[Fiver]

I have one at my work place

How can I get them to fix it correctly to accept a model 3 charge

You need a transformer to bring the 277v down to 208v. Costs a couple hundred bucks plus installation. This was a hold up on one of my destination installs. Site wanted to put in 277v (as that was what was running there already), but Tesla said they now only support 208v so we had to order extra parts and it added time and cost.

 

[MP3Mike]

You need a transformer to bring the 277v down to 208v. Costs a couple hundred bucks plus installation. This was a hold up on one of my destination installs. Site wanted to put in 277v (as that was what was running there already), but Tesla said they now only support 208v so we had to order extra parts and it added time and cost.

It is better if you step the 277v down to 240v, as people can get a ~15% faster charge. (I don't know if it is less common/more expensive to do that.)

 

[Fiver]

It is better if you step the 277v down to 240v, as people can get a ~15% faster charge. (I don't know if it is less common/more expensive to do that.)

It is more expensive to do that.

 

[miimura]

It is more expensive to do that.

Is it more expensive because there are no transformers available off the shelf for that particular voltage ratio? In theory, a smaller ratio requires a smaller transformer, so it should cost less, all else equal.